PETE WILLIAMS: The stretch drive to Iowa, the candidates get tougher on each other, plus the president's valedictory State of the Union, chock full of politics.

I'm Pete Williams in for Gwen Ifill this week on Washington Week.

Oh, it's heating up out there, especially between the two Republican front-runners, on Ted Cruz's birthright.

DONALD TRUMP: (From video.)

If you become the nominee, who the hell knows if you can even serve in office?

PETE WILLIAMS: And on Donald Trump's New York values.

SENATOR TED CRUZ (R-TX): (From video.)

And I guess I can frame it another way.

Not a lot of conservatives come out of Manhattan.

I'm just saying.

PETE WILLIAMS: While on the Democratic side, the question is who's tougher on guns?

FORMER SECRETARY OF STATE HILLARY CLINTON: (From video.)

It's time to pick a side.

Either we stand with the gun lobby or we join the president and stand up to them.

I'm with him.

SENATOR BERNIE SANDERS (I-VT): (From video.)

A candidate who was originally thought to be the anointed candidate, to be the inevitable candidate, is now locked in a very difficult race here in Iowa and in New Hampshire.

PETE WILLIAMS: From President Obama, some introspection as he begins his final year in office.

PRESIDENT BARACK OBAMA: (From video.)

It's one of the few regrets of my presidency that the rancor and suspicion between the parties has gotten worse instead of better.

PETE WILLIAMS: The politics in Washington and out on the campaigns.

With analysis tonight, Karen Tumulty, national political correspondent for The Washington Post; Lisa Lerer, national politics reporter for the Associated Press; Peter Baker, chief White House correspondent for The New York Times; and Manu Raju, senior congressional correspondent for CNN.

ANNOUNCER: Award-winning reporting and analysis.

Covering history as it happens.

Live from our nation's capital, this is Washington Week with Gwen Ifill.

Once again, live from Washington, sitting for Gwen Ifill this week, Pete Williams of NBC News.

PETE WILLIAMS: Good evening.

A president's State of the Union address, especially his last one, would normally be a big deal around this table, but it was upstaged by campaign fireworks.

With less than three weeks before people actually start weighing in on who will be the next president, things were much more lively in both parties.

Before a crowd in South Carolina, the Republican front-runners, Donald Trump and Ted Cruz, sparred last night about Cruz's legal qualification to be president.

DONALD TRUMP: (From video.)

Here's the problem.

We're running.

We're running.

He does great.

I win.

I choose him as my vice presidential candidate, and the Democrats sue because we can't take him along for the ride.

I don't like that, OK?

SENATOR TED CRUZ (R-TX): (From video.)

You know, back in September my friend Donald said that he had had his lawyers look at this from every which way, and there was no issue there.

There was nothing to this birther issue.

(Laughter.)

Now, since September, the Constitution hasn't changed.

PETE WILLIAMS: It continued like that much of the night as the others on that stage tried to assert themselves against the front-runners.

SENATOR MARCO RUBIO (R-FL): (From video.)

Ted Cruz, you used to say you supported doubling the number of green cards.

Now you say that you're against it.

I saw you on the Senate floor flip your vote on crop insurance because they told it you would help you in Iowa.

And last week we all saw you vote your vote on ethanol in Iowa for the same reason.

(Cheers, applause.)

That is not consistent conservativism.

That is political calculation.

FORMER FLORIDA GOVERNOR JEB BUSH (R): (From video.)

We're running for presidency of the United States here.

This isn't - this isn't, you know, a different kind of job.

You have to lead.

You cannot make rash statements and expect the rest of the world to respond as though, well, it's just politics.

PETE WILLIAMS: So, Karen, you were there.

As you watched that debate, did you see any patterns in all that chaos?

KAREN TUMULTY: Yes.

If I looking a little sleep deprived, that's why.

Yeah.

It was - there were two sets of arguments essentially going on on the stage.

One was the one between Donald Trump and Ted Cruz.

This is really interesting because up until now these two candidates have had sort of a nonaggression pact.

Ted Cruz has not wanted to get in Donald Trump's crosshairs because he essentially doesn't want to offend Donald Trump's supporters because the assumption being at some point he explodes and Ted Cruz would be there to catch the support.

Donald Trump was not attacking Ted Cruz because Ted Cruz was saying nice things about him, and because he didn't see him as much of a threat.

Well, now the polls are showing that in fact Iowa is very close between the two of them.

So that was the first drama we had going.

The second one was among the candidates who would like to be the establishment alternative to whichever of the, you know, Cruz-Trump antiestablishment forces ultimately emerges from this.

So that's where you see Chris Christie and Marco Rubio and Jeb Bush all sort of sparring as, you know, I'm the adult, the credible one, I'm the viable one.

PETE WILLIAMS: So two debates in one.

But from what you saw in Iowa while you were there, how did the campaigns differ in style in the state?

KAREN TUMULTY: You know, it's really interesting.

It's like the three leading contenders have three totally different theories of the case.

Donald Trump is essentially figuring - and very untraditionally for Iowa - figuring that, you know, if he has these big rallies people will come to him.

It's almost a "Field of Dreams" strategy.

It's not the way you'd normally run a caucus state.

That is how Ted Cruz is doing it, where he is going to every tiny town on the map, speaking to every voter he could.

And he's got the resources to add the technology component to that as well.

And then a third kind of strategy would be Marco Rubio's, who has not really been out and about in the state all that much, but between now and caucus day, one-third of every single political ad that people in Iowa see is going to be an ad on Marco Rubio's behalf.

PETE WILLIAMS: So let me just ask Lisa a question here.

The sharp-eyed people here in Washington, we counted 30 mentions, some might say shots at Hillary Clinton last night.

So is that strategy working for the Republicans, to attack her at the same time they're attacking each other?

LISA LERER: Well, it's certainly been a popular strategy.

I mean, that number is pretty standard for all of these Republican debates.

She's a very popular, or I guess unpopular figure on the stage.

You know, it's a way for Republicans to rally their base.

They want to show that they're the toughest candidate against this challenger, or this Democrat - potential Democratic general election nominee who Republicans think will a be pretty tough opponent.

It's also, frankly, not something that the Clinton campaign is all that upset with.

They sort of figure that anyone who is voting in the Republican primary is probably not a gettable vote, most likely, for Hillary Clinton.

So having her attacked so much in the Republican debates gives them a way to boost their own base, to send out fundraising appeals, to get their own people excited about a general election by striking that contrast.

MANU RAJU: Karen, you had mentioned the Republican establishment, the sort of people that are vying in that lane.

What was interesting last night was the Rubio versus Chris Christie battle.

Of course, that's been bubbling up for weeks and it's all about New Hampshire, where both men are competing pretty aggressively.

Did you sense any - when you were there, what was the mood like in the room?

Did it feel like Chris Christie got the better of that exchange between the two of them, or did Marco Rubio come out on top?

Or did they end up in a draw on that point?

KAREN TUMULTY: Well, there was a lot of ganging up on Marco Rubio on that stage, not just Chris Christie, but Jeb Bush.

And he and Ted Cruz went at it quite a bit as well.

So I think just in the sheer kind of force of everyone taking after Marco Rubio, it was pretty intense.

But, you know, he's a pretty smooth and skilled debater, so I think he - you know, these were all lines that people who've covered him on the campaign trail have heard many, many times.

But for a television audience, they were essentially seeing Marco Rubio at probably his best.

PETER BAKER: That's why the Democratic debate this weekend, actually, will be interesting, because the dynamic will be exactly the opposite, right?

Instead of having six people on stage, you'll have three but really just two who are genuinely competitive against each other.

I mean, at this point Sanders is surging.

Is that a real threat to Hillary?

How is she responding?

Is that - what footsteps do they hear behind them?

LISA LERER: Well, so one thing - the big question facing Sanders is whether he can expand his base.

So far he's done extremely well with white voters, particularly younger, white, male voters.

And that's a good group to have in states like Iowa and New Hampshire.

Once you get into these later contests - South Carolina, Nevada, the March 1st Super Tuesday states - you need to have a stronghold in the other - within minority voters, who make up a huge swath of the Democratic Party.

It's not clear whether his appeal extends into that group.

He's certainly been trying very hard.

So I would say that Hillary Clinton is still favored to win the nomination.

Historically, of course, that's how it's always worked in Democratic primaries, right?

KAREN TUMULTY: But at the last debate, which was the Saturday night before Christmas, so nobody except those of us who had to be there probably saw it, Hillary Clinton - you wouldn't have known Bernie Sanders was on the stage.

All she wanted to talk about was Donald Trump.

I suspect it's not going to be that way this time now that Bernie Sanders is emerging as a real threat to her in Iowa.

LISA LERER: That's been one of the most interesting things about the Democratic race in this January 2016 period, is that Hillary Clinton has gone from focusing almost exclusively on Republicans - I don't think she ever mentioned Bernie Sanders by name - to focusing really intensely on him.

And it's not just her.

It's the whole campaign apparatus behind her.

Look, even Chelsea Clinton took a dig at Bernie Sanders this week.

Which really indicates how concerned they are about that challenge.

PETE WILLIAMS: Have Hillary Clinton's attacks on Sanders had any effect on his fundraising?

KAREN TUMULTY: (Laughs.)

Yes.

They're loving it, in fact.

LISA LERER: Yeah, she's trying to make a pretty tough case against him.

The case is basically his proposals are unrealistic and that he's disingenuous, that he's not actually this champion of - this fighter against income inequality and fighter against corporate interests, as he says he is.

It's a tough case to make.

The guy has been in the Senate and the House for 25 years on these issues.

It's just going to be a hard case.

PETE WILLIAMS: I want to ask you about one other thing that came up in the debate.

We heard Ted Cruz say earlier that Donald Trump has what he called New York values, and that statement came up at the debate last night.

And then Trump responded.

SENATOR TED CRUZ (R-TX): (From video.)

Everyone understands that the values in New York City are socially liberal, are pro-abortion, are pro-gay marriage, focus around money and the media.

In his explanation, he said, look, I'm from New York.

That's what we believe in New York.

Those aren't Iowa values, but this is what we believe in New York.

DONALD TRUMP: (From video.)

When the World Trade Center came down, I saw something that no place on Earth could have handled more beautifully, more humanely than New York.

And we rebuilt downtown Manhattan.

And everybody in the world watched.

And everybody in the world loved New York and loved New Yorkers.

And I have to tell you, that was a very insulting statement that Ted made.

(Cheers, applause.)

PETE WILLIAMS: So, Karen, did he seem ready for that?

KAREN TUMULTY: I would say so.

It was - in fact, it put Donald Trump into some very unfamiliar territory in this campaign.

He was on the high ground.

(Laughter.)

And - PETE WILLIAMS: And he seemed prepared.

MANU RAJU: He looked like a statesman, too.

LISA LERER: Yeah.

KAREN TUMULTY: And he - and even Hillary Clinton then today issued a statement saying, he's absolutely right about New Yorkers and their values.

LISA LERER: It's been amazing to watch him.

I think he actually improved as a candidate throughout this process.

I don't know if you'd agree.

But it has been a remarkable thing to watch.

PETER BAKER: Did he give - did Cruz dispose of the birther issue, as he called it, or is that going to still be something out there haunting him?

KAREN TUMULTY: You know, I have yet to run across a voter who really cares about this.

But the fact is, Donald Trump is not going to drop it.

MANU RAJU: And you - I want to ask you, back to the Clinton-Sanders question, I mean, look, if Clinton loses Iowa, she could still win the nomination as you suggested.

But how much would that hurt her, the perception that she's the strongest candidate for the party and just, you know, come rallying the Democratic base behind her heading into the general election?

PETE WILLIAMS: Here we go again, right?

MANU RAJU: Yeah, here we go ahead.

LISA LERER: Right.

What her campaign is afraid of isn't so - I mean, obviously losing Iowa or a narrow win in Iowa and a loss in New Hampshire, that's not a good outcome.

But what scares them more, I think, than losing the nomination is the freak out that will inevitably come in the party.

You have a number of people in the Democratic Party who don't particularly care for Hillary Clinton.

They're already sort of primed to seek alternatives.

They're going to start looking around, is there is someone who could jump in late?

MANU RAJU: Biden.

LISA LERER: Top on their list would be Vice President Biden, who gave a - PETER BAKER: He regrets it every day, he says, about not running.

LISA LERER: Right.

He has the capacity to.

PETE WILLIAMS: So talking about the Democratic campaign, it was heating up.

There was some discussion about taxes.

But Sanders also launched a new campaign commercial to chide Hillary Clinton on her connections to Wall Street.

HILLARY CLINTON: (From video.)

A lot of what he's talked about in his campaign would be very expensive.

It would probably, by the best estimates, end up costing $18 to $20 trillion over 10 years.

That's a lot of money.

That would raise the federal budget by 40 percent.

So you deserve to know what the differences are.

SENATOR BERNIE SANDERS (I-VT): (From video.)

There are two Democratic visions for regulating Wall Street.

One says it's OK to take millions from big banks and then tell them what to do.

My plan?

Break up the big banks, close the tax loopholes, and make them pay their fair share.

PETE WILLIAMS: So, Lisa, very quickly, Hillary Clinton said she wanted a campaign not a coronation.

Is she getting one?

LISA LERER: Be careful what you wish for.

(Laughter.)

She's getting a real campaign.

Certainly in Iowa, certainly New Hampshire, as is Sanders.

He's, of course, made this pledge not to go negative - a central focus of his candidacy.

And it's really a central part of his brand.

That could get tricky in the days to come, particularly as this race gets nastier.

PETE WILLIAMS: All right.

Well, thank you.

Moving on here.

Thank you both.

If you were watching the State of the Union message, toward the end it certainly looked to me like the president seemed to linger for one more look at the House chamber after his final State of the Union address this week.

Usually it's a long to-do list, but this one - seen, by the way, by the smallest audience for one of these speeches in 20 years, had a distinctly different tone.

PRESIDENT BARACK OBAMA: (From video.)

Let me start with the economy and a basic fact.

The United States of America, right now, has the strongest, most durable economy in the world.

Anyone claiming that America's economy is in decline is peddling fiction.

PETE WILLIAMS: He reviewed the accomplishments of his seven years in office, but he also criticized a certain Republican front-runner.

PRESIDENT BARACK OBAMA: (From video.)

When politicians insult Muslims, whether abroad or our fellow citizens, when a mosque is vandalized or a kid is called names, that doesn't make us safer.

That's not telling it what - telling it like it is.

It's just wrong.

PETE WILLIAMS: South Carolina Governor Nikki Haley, who delivered the Republican response, echoed some of those same sentiments.

SOUTH CAROLINA GOVERNOR NIKKI HALEY (R): (From video.)

During anxious times, it can be tempting to follow the siren call of the angriest voices.

We must resist that temptation.

No one who is willing to work hard, abide by our laws, and love our traditions should ever feel unwelcome in this country.

PETE WILLIAMS: Beyond that, she didn't agree much with President Obama but, Peter, was this actually the president's first 2016 campaign speech?

PETER BAKER: Well, in a way, that's right.

There are two different campaigns he was waging here that night.

One is for history, right?

He's trying to set out his case for why his presidency was a success.

The economy is much better.

We're making some progress, he says, on foreign affairs.

Health care obviously expanded across the board.

And then he's making a campaign speech in effect not just for Hillary Clinton, but for himself in this campaign, because he is the target of so many of these attacks.

Two days later, you heard Hillary Clinton's name a lot on stage but you heard Obama's name on stage a lot, too.

So he was engaging in effect before the debate even got started by saying: What you're going to hear is a lot of gloom and doom from these guys, talking down America.

I'm here to tell you, America's great and don't let them tell you otherwise.

So he was trying to engage on this concept.

And the concept is important, because what do Americans believe?

Do they believe the country is on the right track or not?

Polls show they don't believe it.

Two to one, Americans believe we're on the right track, and they have for a while.

PETE WILLIAMS: On the wrong track, you mean.

PETER BAKER: On the wrong track, sorry.

They believe we're on the wrong track, and they have for a while.

For 12 years - it's been 12 years since more Americans believed we were on the right track than on the wrong track.

That's a pretty sustained period of pessimism on the part of Americans.

And he's trying to now talk them out of it.

PETE WILLIAMS: Well, I guess it depends what numbers you look at.

But if you compare his rather rosy scene with the Republican sort of gloomy scene, who's right?

PETER BAKER: Well, each side, of course, has numbers to point to.

The president has probably an easier case on the domestic side, in the sense that the economy is doing better.

They had 2.3 million jobs created last year.

The unemployment's down to 5 percent, and so on.

On foreign affairs, it's a little tougher because, you know, the world seems to be blowing up all over the place, and he's trying to point to a lot of agreements but they're wondering what's happening with ISIS, what's happening in Ukraine, places like that.

KAREN TUMULTY: Yeah, I was struck in the first lady's box there was an empty seat for victims of gun violence, but there were also a number of people there who were meant to sort of remind you of the high points of the Obama presidency.

What did he - did he lay the predicate for governing for the rest of his term?

Or was this in fact about the legacy?

PETER BAKER: Well, there really isn't very much he can do in Congress.

Manu knows that better than I do.

He'd like criminal justice reform.

There is an opportunity there for Republicans to come together with him on this.

Obviously, he'd like his trade deal that he's negotiated in Asia.

But what he really understands is that, for his presidency to be successful, it would be most helpful to have a Democrat follow him because then it will remove the threat to repealing health care, for instance.

And so I think he's thinking very long term in that regard.

PETE WILLIAMS: So, Manu, what about that?

I mean, other than criminal justice reform, is there anything the president can get out of this Congress in the coming year?

MANU RAJU: I doubt it.

I mean, the trade agenda that Peter was just referring to is supported by Republicans largely and broadly.

Remember, last year they passed the fast track trade agreement called Trade Promotion Authority that would actually lead to the passage of this massive trade deal, the Trans-Pacific Partnership.

The problem is that we didn't see the details of the Trans-Pacific Partnership until late last year, or actually until the beginning of this year, and now a lot of Republicans are getting a little squeamish about the details.

Mitch McConnell, the Senate majority leader who supported - was a big trade supporter, says that it's probably not a good idea to do the Trans-Pacific Partnership this year.

And Paul Ryan, who's a huge trade supporter - the House speaker - also has not yet lent his support behind this deal.

So this could probably be hanging out until the next administration.

They could take it up - and the next president.

But who knows; the next president, if it's Hillary Clinton, she came out against the deal, even though she supported it as secretary of state.

So that's a long way of saying that there's very little that will get done this Congress, other than possibly criminal justice reform.

But mostly both parties will be making their case why they should stay in power.

LISA LERER: On the campaign argument side of things, was that effective?

I mean, was anyone listening to the speech?

Do you think that he laid out the case for the Democrats in an effective way that will benefit them in 2016?

MANU RAJU: I think that - when I was talking to a lot of Democrats as they were leaving the chamber, they were like - they were saying to me, where was this guy in the last several years?

They like that kind of speech, that really rosy, optimistic speech.

They felt like they were missing that in the 2014 midterms.

They thought that that argument could have been made a little bit more aggressively.

So certainly I think that they - that that could help.

But as we know, very quickly the focus shifted back to the campaign trail.

How much the president will have a bully pulpit for the rest of this year is probably not nearly as much as he's had in the past.

PETE WILLIAMS: Peter, what else does the president want out of this Congress?

Or does he realize that, really, beyond that one thing we talked about, there really isn't much?

PETER BAKER: Well, look, he's got a budget deal in place so he doesn't have to worry about that.

That's a big deal.

We won't have the kind of fights over a possible shutdown that we've had in the past.

And so what he really wants is for them to stay out of the way, I think.

You know, he's going to be on a plane a lot.

You're going to see him get out of the country five, six times this coming year.

He's going to be a foreign policy president.

He's going to have to try to make the argument that his foreign policy has made a difference - and we're talking about the Iran nuclear deal, which we're going to see this very weekend possibly come into force; the Cuba opening; the climate pact; and so on.

And the trade deal is his other one.

So he wants to, you know, use Air Force One, basically, as his launching pad.

MANU RAJU: And I would say so much of it is each - you know, the White House wants to implement the rest of its agenda.

They're going to aggressively try to get a lot of these executive actions that they have launched, get that done.

And the House Republicans in particular want to showcase what they would do if they had both houses of Congress as well as the White House.

Paul Ryan was pushing to lay out a bunch of detailed proposals, including what they would actually do on health care.

They have not had a plan to replace Obamacare.

Presumably they'll come out with that.

Now, that will never pass - that will never get signed into law by the president, probably won't pass the Senate, but they want to make this the argument heading into November.

PETE WILLIAMS: So if - the question was about what President Obama expects to get out of this year.

What does Paul Ryan expect to get of this year?

MANU RAJU: I think that's it.

He wants to make the - it's all about making the case to voters on what we would do if we got the majority.

So it's all a political argument.

I was up in Baltimore this past week, where House and Senate Republicans were meeting and discussing the way forward for this year.

And they all - they know there's very little they can do legislatively, but they want to lay out the specific agenda on what they would do if they were still in power in 2017.

And why that's different is because in the past most of these guys, they go home and they campaign, they don't do much legislatively, they don't want to get into the details of things that could get them in a tough position.

Paul Ryan wants to actually lay out, say what we'll do on welfare reform, what we'll do on tax reform, what we'll do on health care reform, and run on that.

The difference I will add, though, is that Senate Republicans don't necessarily want to do that because 24 of them are up for reelection this year, particularly in tough states, and they don't want to get into the intricacies of health care reform.

PETE WILLIAMS: Very briefly.

PETER BAKER: Well, the truth is, who's actually speaking for the party right now, Paul Ryan, or Donald Trump and Ted Cruz?

MANU RAJU: And that's where the struggle is, who is - who is the face for the party?

Paul Ryan wants it to be him, where they present a more rosy, optimistic - rosy view of America.

PETE WILLIAMS: Very, very quickly, the president seemed relaxed after the speech.

Will we see that same relaxed style the rest of the year?

PETER BAKER: I think a little bit.

He was relaxed on the road a couple days after the speech and kind of joking around.

Somebody asked him, you should run for a third term.

He says, I can't because of the Constitution, but I really can't because Michelle would kill me.

I mean, he was in a pretty - he's not on the ballot, right?

It must be a lot easier.

PETE WILLIAMS: All right.

Thank you all.

Thank you very much.

That will have to do it for tonight.

But if you didn't get enough, we'll have more on the Washington Week Webcast Extra, where we'll look at the other Republican candidates who didn't make it to the big guys table and what their staying power might be.

That's later tonight at PBS.org/Washington Week.

I'm Pete Williams.

Gwen will be back here next week on Washington Week.

Good night.